+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   774 Armor (A913 YE) Classification: Main-belt Asteroid          SPK-ID: 2000774 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 56 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1672171708478123 3.7604e-08   a 3.048649677582373 1.1997e-08 au q 2.538863103590953 1.137e-07 au i 5.565809032059367 4.1439e-06 deg node 250.1178560187641 3.9369e-05 deg peri 28.50753866547278 4.0881e-05 deg M 139.9180852505062 1.2225e-05 deg tp 2458244.831946190509 (2018-May-06.33194619) 6.5033e-05 TDB period 1944.284035079251 5.32 1.1476e-05 3.142e-08 d yr n .1851581319934698 1.0929e-09 deg/d Q 3.558436251573792 1.4003e-08 au   Orbit Determination Parameters    # obs. used (total)      3463      data-arc span      40876 days (111.91 yr)      first obs. used      1908-12-16      last obs. used      2020-11-14      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .43259      source      ORB      producer      Otto Matic      solution date      2020-Dec-18 01:56:02   Additional Information  Earth MOID = 1.52418 au   Jupiter MOID = 1.57658 au   T_jup = 3.209  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 8.8   n/a MPO319091   diameter diameter 50.214 km 0.457 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 25.194 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Behrend, R. (2005) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] [Warner, B.D.; Higgins, D.; Bennett, M.; Fauerbach, M. (2006) Minor Planet Bull. 33, 95.] [Oey, J.; Han, X.L.; Gipson, K. (2013) Minor Planet Bull. 40, 64.] [Polakis, T. (2020) Minor Planet Bull. 47, 94-101.] geometric albedo albedo 0.189   0.029 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)   774 Armor (A913 YE)          Discovered 1913-Dec-19 by Le Morvan, C. at Paris Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  A913 YE = 1955 SW2 = A896 RA = A908 YH = A910 CJ  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-21 06:45 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin